1. Field of the Invention
The present invention relates to a bicycle hub generator. More specifically, the present invention relates to a bicycle hub generator provided in a center portion of a wheel of a bicycle configured to deliver electric power to an external device mounted to the bicycle.
2. Background Information
A conventional hub provided at a center portion of a wheel of a bicycle generally includes a hub shaft, a hub body and a bearing. The hub shaft is mounted in a freely detachable but non-rotatable manner to the frame (e.g., front fork or chain stay) of the bicycle. The hub body is mounted in a freely rotatable manner to the hub shaft. The bearing is configured to support the hub body in a freely rotatable manner on the hub shaft. The hub body usually has a pair of hub flanges, i.e., one on the outer circumference of each end of the hub body, configured such that the spokes of the wheel can be hooked thereto.
The conventional bicycle hub explained above is sometimes equipped with a hub generator such as the one disclosed in the Japanese Laid-Open Utility Model Patent Publication No. 48-103805 (microfilm of Utility Model Patent Application No. 47-028241). The hub generator disclosed in the above mentioned reference has an electricity generating mechanism that is built into the hub body to serve as an electric power source for a lamp or other external device of the bicycle. By building the electricity generating mechanism into the hub body in this fashion, electricity can be generated without contacting or sliding against a rotating portion. Thus, the electric generating efficiency improves and the wheel rotation loss decreases in comparison with electricity generating devices that contact the rim of the wheel. A conventional hub generator uses wires to deliver the electric power generated by the electricity generating mechanism to the lamp or other external device of the bicycle. In the above mentioned reference, the wires pass not along the outer circumference of the hub shaft but through a hole formed through the center of the hub shaft and the wires are drawn out from the end of the hub shaft.
Accordingly, with the conventional hub generator disclosed in the above mentioned reference, the wires are passed through the inside of the hub shaft. Therefore, it is easier to protect the wires than a case in which the wires are passed along the outside circumference of the hub shaft. However, since the wires that are drawn out from the end of the hub shaft are exposed to the outside, the wires are not protected and could possibly be broken. A feasible solution is to provide a cover member on the end of the hub shaft to cover the wires drawn out from the end of the hub shaft. However, in order to mount the cover member, a separate mounting structure is required and the structure of the hub generator becomes more complex.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved bicycle hub generator that can protect the wires that are drawn out from the end of the hub shaft with a simple structure. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.